1. Field of the Invention
This invention relates to semiconductor components in general and specifically to semiconductor components of an integrated circuit that are dielectrically isolated from each other.
2. Description of the Prior Art
In the conventional method of fabricating power transistors, silicon controlled rectifiers, and other high power components of an integrated circuit, a plurality of semiconductor regions are ohmically connected in parallel with metal interconnections such that common semiconductor regions are interdigitatedly connected or are connected alternately in some geometrical fashion in order to handle the high power requirement of such components. These interdigitated regions, making up a semiconductor device or semiconductor component in dielectrically isolated material, are normally isolated from other semiconductor components in the same substrate by a layer of dielectric insulation that surrounds each component in the substrate and intersects a surface of the substrate.
In one method of reducing the collector resistance of a power transistor, for example, a highly doped, high-conductivity collector contact region of the same conductivity type as the collector is normally formed inside of the surrounding insulating layer and adjacent thereto. The highly doped collector contact region also intersects the same surface of the substrate where ohmic contact can be made directly to the high conductivity region or into another highly doped, high-conductivity region of the same conductivity type which has been diffused into the surface of the substrate at the intersection of collector contact region and surface. Since the collector contact region only surfaces at the periphery of the component, due to its inherent structure, there is a limit as to the degree of reduction of collector resistance.
Accordingly, an object of this invention is to provide a method of fabricating dielectrically isolated semiconductor components of an integrated circuit having high conductivity paths to selected semiconductor regions.
Another object of this invention is to provide a method of fabricating dielectrically isolated transistor components of an integrated circuit, each transistor having a plurality of ohmic contacts to collector contact regions at selected locations.
A further object of this invention is to provide a dielectrically isolated semiconductor component of an integrated circuit having high conductivity paths to selected semiconductor regions.
Yet another object of this invention is to provide a dielectrically isolated transistor component of an integrated circuit having a plurality of ohmic contacts to the collector contact region at selected locations.